1. Field of the Invention
The present invention relates to a communication device for communication via a telephone line.
2. Description of the Related Art
Communication devices, such as telephones or facsimile machines, communicate with communication partners via telephone lines. There are multiple telephone line standards in the world, and the standards specify different line impedances of telephone lines. The terminal impedance of a communication device as seen from a telephone line is often set to a value corresponding to the line impedance of the telephone line (e.g., Japanese Patent Application Publication No. 2010-171636).
However, the communication quality of a communication device may be degraded.